On Sun, Mar 03, 2013, Norman Baugher wrote: > > How about when they ask you what type of credit card you are using > when in actuality, the first digit of the number denotes the card > type?
Although you're right in this particular case, I'm somewhat sympathetic to the desire for "check digits" in user input (i.e. if user enters card number different from type you can flash an error -- but that's really not necessary for credit cards because you're supposed to use online validation direct to the credit card company). On the gripping hand, you can do the cross-check locally without pinging the credit card company which speeds up user response to the error condition. Similarly, if you're only allowing US addresses, you don't need the state if you're getting the ZIP codes (ZIP codes cross every single legal boundary in the US except states AFAIK). But the cross-check is still useful. The relevance of this mentality to photography is left as an exercise for the reader. ;-) -- Hugs and backrubs -- I break Rule 6 http://rule6.info/ <*> <*> <*> Help a hearing-impaired person: http://rule6.info/hearing.html -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
